One constant in modern world affairs is that nations protect their territorial integrity, even at great cost.
Can you think of any instances in the last 200 or so years - the more recent, the better - in which a country decided it would be better off with less land? In which a country actually took the initiative to get rid of a certain territory?
Decisions made under great duress (like as the result of a war or a secessionist movement) don’t count. Nor does decolonization.
(I suppose the Louisiana Purchase and the sale of Alaska count to some extent, although they brought some monetary reward to the nations that sold them.)
The expulsion of Singapore from Malaysia in 1965 is close to what I’m after, although Singapore actually hadn’t been part of Malaysia for more than a couple of years before then.
As American farmers/settlers/pioneers moved into California, when California was still part of Mexico, they wished that the region would become part of the United States. By and by, a group in the Sonoma area proclaimed independence and proclaimed the California Republic, a.k.a. the Bear Flag Republic. This lasted for a prodigious 26 days, but before they ever really got a working government set up, they chose to join with the rest of the United States. Which, of course, is no doubt what they intended all along.
Of course, what I’ve written above is not exactly the way it’s usually told (but close) – but my interpretation is, that’s what was really going on.
I think the same sort of thing was going on when American businessmen overthrew the Hawaiian monarchy and proclaimed an independent Hawaii, which rather promptly became a United States territory. Again, that’s at least in part my interpretation of what I’ve read.
Both Egypt and Sudan are both eager to give up Bir Tawil but because both believe that not owning that territory would give them a better claim on more valuable land, I’m not sure if this is what the OP is looking for.
Like you said, it applies to a great majority of the U.S. by land area. That isn’t just a footnote either. The most powerful country on Earth was built on tremendous amounts of land so cheap and deemed useless by its previous owners that it was essentially free. Not mentioned yet is that the U.S. got the U.S. Virgin Islands for a relative song from the Dutch. It isn’t the most productive land in the world but it sure is pretty. The U.S. still holds a large part of Cuba in Guantanamo Bay that wasn’t won through any war. It was gotten through a cheap lease and had been free for many decades because Castro refuses to cash the payment checks.
I don’t think you will find too many stories of ‘Free to Good Home’ signs when it comes to nations. Everything has some worth but the U.S. was built on land that often sold for just a penny or two an acre.
IIRC the perpetual lease for Hong Kong was only for the island. The city had spread and integerated into the New Territories enough that you simply could not just draw a line down the middle of the harbour and make it two countries. Too many things and people had feet on both sides - electrical supply, water supply, etc. If the locals had decided they all wanted to stay British, there would have been a disruptive flood of people onto the island with nowhere to put them all, the economy would collapse, etc.
But yes, it was a willing decision, although the pressure to keep things working was real.
It looks like Russia wanted to get rid of Alaska because they were afraid that they would lose it by conquest in a future conflict with Britain and actually approached both Britain and the US hoping for interest. Selling it then would at least give them some money. If they lost it to war they would get nothing.
Along the same lines, the Dominion of Newfoundland (which had been de jure independent for over 40 years, though its de facto level of independence from the UK varied) joined Canada in 1949 after a referendum.
Britain essentially does not like, want or need the Falkland Islands. They would have been happy to hand over the territory to Argentina decades ago. But the Islanders have refused, wishing to stay British, and the government can’t lose face by going against their wishes.
There was very little enthusiasm in Washington for the US ruling over a colony filled with millions of poor non-Whites. There was even less enthusiasm at the prospect of these subjects eventually demanding statehood.
That may change with recent natural gas & oil discoveries combined with advances in deep sea drilling technology.